1. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
Simplify the expression 10 – 17.
10 – 17 = 10 + (–17)
Add the opposite of 17, which is –17.
Simplify.
= –7
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2. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
The elevation of the Dead Sea is 396 m below sea level. A group of archaeologists leaves the shore of the Dead Sea and heads toward Jordan. They stop after ascending 500 m. What is their elevation?
Draw a diagram.
The diagram shows that the elevation of the archaeologists is given by
the expression –
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3. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
(continued)
– = 104
Simplify by using the rule for adding integers with different signs.
The elevation of the archaeologists is 104 m above sea level.
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4. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
Evaluate y – 38 for y = –5.
y – 38 = –5 – 38
Substitute –5 for y.
= –5 + (– 38)
Add the opposite of 38, which is –38.
= –43
Simplify.
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5. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
Simplify each expression.
1. 11 – (–6) 3. –1 – (–20)
4. 15 – –4 + (–6) 6. 9 – (–2) –6 2 19 3
–10 11
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